This invention relates to methods for treating a well bore or pipeline. More particularly, but not by way of limitation, this invention relates to methods for collecting heat from multiple engines and heating fluids and thereafter placing the fluids in a well bore or pipeline for purposes of treating the well bore or pipeline.
In the exploration and development of hydrocarbon reservoirs, a well is drilled to a subterranean reservoir, and thereafter, a tubing string is placed within said well for the production of hydrocarbon fluids and gas, as is well understood by those of ordinary skill in the art. As the search for additional reserves continues, offshore and remote areas are being explored, drilled and produced with increased frequency. During the production phase, the production tubing and pipelines may have deposited within the internal diameter such FLUIDs as paraffin, hydrates, asphaltines, and general scale which are precipitated from the formation fluids and gas during the temperature and pressure drops associated with production.
Both the treatment of tubing string and the pipelines may be accomplished by the injection of specific fluids. The effect of the treating fluids will many times be enhanced by heating the treating fluid. Thus, for the treatment of paraffin and asphaltines, the heating of a specific treating fluids (e.g. diesel) enhances the removal.
In order to heat these types of fluids, operators frequently utilize an open or enclosed flame. However, government regulations have either banned or limited the use of open or enclosed flames on offshore locations and some land locations. Thus, there is a need for a thermal fluid unit that will heat a treating fluid without the need for having an open flame. There is also a need for a method of treating well bores with a heated treating fluid.
A method of heating a treating fluid used in a well bore having a tubing string or a pipeline is disclosed. The method will comprise providing a diesel engine that produces heat as a result of its operation. The engine will in turn produce a gas exhaust, a water exhaust, and/or a hydraulic oil exhaust from the primary engine of this invention and will further scavenge gas exhaust, water exhaust, and/or hydraulic oil exhaust from one or more other engines in the area.
The method would further include channeling the gas exhaust to a gas exhaust heat exchanger, and channeling the water exhaust to a water exhaust heat exchanger. The method may also include producing a hydraulic oil exhaust from the diesel engine and channeling the hydraulic oil exhaust to a hydraulic oil heat exchanger. Next, the treating fluid is directed into the hydraulic oil heat exchanger, and the treating fluid is heated in the hydraulic oil heat exchanger.
The method may further comprise flowing the treating fluid into the gas exhaust heat exchanger and heating the treating fluid in the gas exhaust heat exchanger. The operator may then inject the treating fluid into the well bore for treatment in accordance with the teachings of the present invention.
The treating fluids may be fluids taken from the well bore or pipeline and simply recirculated after being heated by apparatus of the present invention. Alternately, the treating fluids may be a variety of other fluids, including diesel fuel, hydrochloric acid, hydrofluoric acid, or other processed hydrocarbons.
Also disclosed herein is an apparatus for heating a treating fluid used in a oil and gas well bore or pipeline. The apparatus comprises a diesel engine that produces a heat source while in operation. The engine has a gas exhaust line, and a water exhaust line. The apparatus further includes a water heat exchanger means, operatively associated with the water exhaust line, for exchanging the heat of the water with a set of water heat exchange coils; and, a gas heat exchanger means, operatively associated with the gas exhaust line, for exchanging the heat of the gas with a set of water heat exchange coils.
The apparatus may also contain a hydraulic oil line that has operatively associated therewith a hydraulic oil pump means for pumping hydraulic oil from the engine into the hydraulic oil heat exchanger and further associated therewith a hydraulic back pressure control means for controlling the back pressure of the engine.
The apparatus may also contain means for connecting to other engines in the area of the primary engine which collect some portion of the heat from the water exhaust, gas exhaust, or hydraulic exhaust from the other engines.
An advantage of the present invention is that it allows a relatively small engine to drive the operation of the thermal module, and allows larger and more expensive engines in the area to provide a percentage of the heat to heat the treating fluids. As this heat is normally dumped to the environment, it is effectively getting a supply of heat for no cost, other than connecting to it.
Another advantage of the present invention includes it effectively removes paraffin, asphaltines and general scale deposits through the novel heating process. Another advantage is that fluids are heated in a single pass with continuous flow at temperatures of 180 degrees Fahrenheit up to and exceeding 300 degrees Fahrenheit without the aid of an open or enclosed flame. Yet another advantage is that because of the elimination of the open flame, the operator is no longer limited to use of heated water and chemicals for cleaning tubing and pipelines i.e. hydrocarbons can be used as the treating fluid to be heated.
Another advantage is that hydrocarbons (such as diesel fuel) can be applied through the novel apparatus without the danger of exposure to open or enclosed flames. Yet another advantage is that with the use of heated hydrocarbons, the chemical consumption can be greatly reduced thus providing an economical method for paraffin and asphaltine clean outs. Of course, the novel system can still be used as means for heating chemicals and water for treatment of the tubing, pipeline, or alternatively, stimulating the reservoir.
A feature of the present invention is the system may be used with coiled tubing. Still yet another feature is that the system is self-contained and is readily available for transportation to remote locations with minimal amount of space.
The object of this invention is to provide a module for the heating of a treating fluid for the purpose of servicing oil and gas wells and pipeline.
A second object of the present invention is utilize as small an engine as possible for the construction of the unit to reduce the cost of manufacture of the unit and the size of the unit.
A third object of the present invention is to supplement the heat generation of the relatively small engine of the unit with other the scavenging of rejected heat of larger engines typically a part of oil and gas service operations.
Another object of the present invention is offer the versatility of supplementing the heat generation of the small engine with the ability to scavenge radiator heat and/or exhaust gas heat and/or crankshaft torque energy from the adjacent engines as most easily suits the situation at the time.
Another object of the invention is have the treating fluid storage and treating fluid pressure pumping means separate from the thermal module to reduce the size and cost of the thermal module.